The invention relates to the field of power recycling power supplies. More particularly, the present invention relates to a system for controlling and recycling power in electronic devices such as power supplies, power converters, and electrical devices.
As the computer and communications industries continue to expand, there will be an increased need for better utilization of electric power. At the same time, the electric utility supply grid is seeing an increase in the demand from electric power by power consuming components. To recycle power, some power systems have flushed excess power back to the utility power grid. During the testing of power systems, it is also desirable to have an ability to accurately measure the performance of each power consuming component or device to verify that power parameters are within specified tolerances with a minimal use of electric power by power supply systems and devices.
Prior power supply systems have used a variety of components for improved power delivery, stability and consumption. Power systems have used power converters with active power factor correction with near unity power factor of the input power absorbed from the utility grid, have used transient stabilizers for stabilizing power input lines and power output lines, have used over and under voltage and current protection, and have used power controllers for controller delivery to power supplies under tests and other electronic devices and loads. The consumption of power during testing of power supplies can be large. Many devices, such as power supplies under test and commercial electrical devices and appliances also require electrical energy that is partially wasted.
The ratio of energy used to power the electrical devices over the total power consumed is the power efficiency. That is, the system performance can be measured as the ratio of the output power of the system under test to the input power from the utility grid. Often power is wasted in the loads attached to power supplies resulting in low power efficiency. The higher the efficiency ratio, the more energy savings. Hence, power supply system designers have long sought to improve the power efficiency of power supplies and power systems as well as all electrical devices and loads.
In conventional testing and validation applications of power supplies, the cost of the power conversion systems that are designed for very high power applications, dramatically adds to the overhead cost of product development. The test loads consume all of the input energy resulting in heat generation during testing that can further increase the total power consumption of a test facility, such as through the use of required air conditioning. This resulting power utilization further contributes to the overhead expense of the testing operation. It is desirable to have test electrical systems and loads provide significant cost savings based on actual reduced total energy usage. Recycling load power of a power system can significantly reduce the power consumption from the utility grid. Some power generators recycle stored energy in fly wheels during utility power outages. However, most power supplies, electronic systems, and electrical devices receive input power used to operate load devices, but then waste energy by failing to recycle excess energy in the load devices. These and other disadvantages are solved or reduced using the present invention.
An object of the invention is to provide a system for recycling power.
Another object of the invention is to provide a system for recycling electrical energy.
Yet another object of the invention is to provide a system for recycling electrical energy used in power supplies under test.
Still another object of the invention is to provide a system for recycling electrical energy in electrical loads.
A further object of the invention is to provide a system for recycling electrical power in an electronic device having an auxiliary power output for feeding back electrical energy to the power input of the electronic device.
Yet a further object of the invention is to provide recycling of electrical energy in an electromechanical or electrooptical device having an auxiliary power output for feeding back electrical energy to the power input of the device.
The system is directed to recycling power passing through an power system and an electrical load that receives electrical energy from a power source and provides an auxiliary output feeding back electrical energy to the electrical power input of the power system. In a preferred form, the power system can be an electrical system under test, such as a power supply having a power input and a load output driving a load with a load auxiliary output fed back to the input of the power supply for reusing the fed back electrical energy that would otherwise be wasted.
In the preferred form, the system uses a smart electronic load that absorbs the output power from the system under test with controllable load characteristics. Transient stabilizers can be used for ensuring reliable power system stability with the transient stabilizers terminated across a feed back path extending from the auxiliary output of the load to the input of the test system. Under and over voltage and current limiters can be also used for improved stabilization in the preferred form. For example, a transient stabilizer can have an input voltage limiter that is used for limiting the input voltage. A power factor correction converter can be also used for improved power efficiency delivery to the system under test, in the preferred form. The system provides a unidirectional power flow between the utility grid and the system under test and load, and therefore, simplifies the design of the recycled power testing system without flushing the recycled power directly back into the utility power grid.
The system enables economical testing of DC-to-DC power converters with significant saving of the electrical energy usage in a DC-to-DC converter system. The system also enables energy savings in any device equipped with an auxiliary output for feeding back unused energy to the power input. Hence, the system has wide applications to power supply testing as well as any electrical device modified for feeding back unused energy. These and other advantages will become more apparent from the following detailed description of the preferred embodiment.